Altruism, as defined here, is an operational concept based on the giving of measurable goods or sevices by an individual to another who is neither mate nor offspring. Kinship theory predicts that altruism will be in proportion to genetic relatioship when gains and losses are in terms of individual fitness. In this study genetic relationship and age are determined by marking parents and their offspring to enable individual recognition. Observations will then be made at yearly intervals to measure age-specific altruism, survival, reproduction, and dispersal. To determine if groups with more altruists are more successful than groups with fewer altruists in one species, Aphelocoma ultramarina, the reproductive success and group size of 33 communal groups will be observed.